Are my spongy brakes normal?
06-24-2012, 09:35 AM
#61
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then i saw you again. wtf are you doing here still?
06-24-2012, 11:25 AM
#63
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Now that you mention the calipers, when I changed my brakes I smothered them with some cheap valvoline silicon grease. It's very tacky, thick stuff.
What I feel when I brake is a delay in the brakes engaging. If I press hard, it takes a second or so for the braking to become more stiff.
I think my calipers themselves are fine-- I probably need to degrease them and put on a grease (lithium grease?) that will allow for smoother sliding of the calipers. Wait, no, you're not supposed to do lithium grease because it will eat away the rubber socks/covers for the brake calipers that slide in/out as you brake. Hm.
What I feel when I brake is a delay in the brakes engaging. If I press hard, it takes a second or so for the braking to become more stiff.
I think my calipers themselves are fine-- I probably need to degrease them and put on a grease (lithium grease?) that will allow for smoother sliding of the calipers. Wait, no, you're not supposed to do lithium grease because it will eat away the rubber socks/covers for the brake calipers that slide in/out as you brake. Hm.
yes you are correct! silicone grease is INCORRECT for the tC calipers. the correct stuff is called "Lithium Soap based glycol grease". The Toyota dealer can find it under P/N 08887-01206, their listing will say "rubber grease". It's a pink grease, and it's the right stuff. I've said it many times in these posts but it's like lots of people don't listen? But just helping you out as you see that over time the silicone grease gets "gummy" and "sticky" where you're not getting the right braking action from the caliper. yes, you will have to degrease and clean out all that silicone from all the caliper pin surfaces.
you don't use regular lithium grease (i know you know that, just saying), the stuff from toyota is different, i've been using it, and the brake feel is VERY responsive and has great pedal feel (not mushy at all, was mushy with silicone grease the dealer lied about and said it was the correct stuff, nope not even close)..
Oh and i think a tube of this stuff cost me at the dealer about $13 and they had to special order it. I think a tube of it lasted me about 2-3 years, I like to lube the caliper pins up every year.
06-29-2015, 02:26 PM
#64
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Are my spongy brakes normal?
There is a simple solution to this problem, which I experienced after replacing the pads & rotors and rebuilding the calipers on my daughter's 2009 tC. The spongy pedal is indeed caused by air in the lines. You won't solve the issue just by power bleeding either.
The real problem is the air in the brake lines at the ABS block under the hood on the passenger side of the engine compartment. You can't miss it. It has six brake lines attached to it.
After bleeding the lines the old way, using a second person to pump and hold down the pedal before loosening each bleeder valve at each caliper in the following order....PR, DR, PF, DF....you now end up with the mushy pedal. Now go under the hood and have your helper pump up the pedal again. It would be best if you could get your hands on a 10mm "Line Wrench" for this next step. Locate the six lines and their associated nuts. Loosen each nut while the pedal pressure is being applied. As each nut is loosened, you will probably hear a rush of air or see bubbles escaping at the nut. When they stop, re-tighten each nut and repeat until there are no more bubbles or air. Repeat for each line. After this is done, check your pedal. Should be back to "like new" condition (hard pedal).
The real problem is the air in the brake lines at the ABS block under the hood on the passenger side of the engine compartment. You can't miss it. It has six brake lines attached to it.
After bleeding the lines the old way, using a second person to pump and hold down the pedal before loosening each bleeder valve at each caliper in the following order....PR, DR, PF, DF....you now end up with the mushy pedal. Now go under the hood and have your helper pump up the pedal again. It would be best if you could get your hands on a 10mm "Line Wrench" for this next step. Locate the six lines and their associated nuts. Loosen each nut while the pedal pressure is being applied. As each nut is loosened, you will probably hear a rush of air or see bubbles escaping at the nut. When they stop, re-tighten each nut and repeat until there are no more bubbles or air. Repeat for each line. After this is done, check your pedal. Should be back to "like new" condition (hard pedal).
06-29-2015, 06:23 PM
#65
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yes you are correct! silicone grease is INCORRECT for the tC calipers. the correct stuff is called "Lithium Soap based glycol grease". The Toyota dealer can find it under P/N 08887-01206, their listing will say "rubber grease". It's a pink grease, and it's the right stuff. I've said it many times in these posts but it's like lots of people don't listen? But just helping you out as you see that over time the silicone grease gets "gummy" and "sticky" where you're not getting the right braking action from the caliper. yes, you will have to degrease and clean out all that silicone from all the caliper pin surfaces.
you don't use regular lithium grease (i know you know that, just saying), the stuff from toyota is different, i've been using it, and the brake feel is VERY responsive and has great pedal feel (not mushy at all, was mushy with silicone grease the dealer lied about and said it was the correct stuff, nope not even close)..
Oh and i think a tube of this stuff cost me at the dealer about $13 and they had to special order it. I think a tube of it lasted me about 2-3 years, I like to lube the caliper pins up every year.
you don't use regular lithium grease (i know you know that, just saying), the stuff from toyota is different, i've been using it, and the brake feel is VERY responsive and has great pedal feel (not mushy at all, was mushy with silicone grease the dealer lied about and said it was the correct stuff, nope not even close)..
Oh and i think a tube of this stuff cost me at the dealer about $13 and they had to special order it. I think a tube of it lasted me about 2-3 years, I like to lube the caliper pins up every year.
06-29-2015, 06:26 PM
#66
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Join Date: Mar 2010
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There is a simple solution to this problem, which I experienced after replacing the pads & rotors and rebuilding the calipers on my daughter's 2009 tC. The spongy pedal is indeed caused by air in the lines. You won't solve the issue just by power bleeding either.
The real problem is the air in the brake lines at the ABS block under the hood on the passenger side of the engine compartment. You can't miss it. It has six brake lines attached to it.
After bleeding the lines the old way, using a second person to pump and hold down the pedal before loosening each bleeder valve at each caliper in the following order....PR, DR, PF, DF....you now end up with the mushy pedal. Now go under the hood and have your helper pump up the pedal again. It would be best if you could get your hands on a 10mm "Line Wrench" for this next step. Locate the six lines and their associated nuts. Loosen each nut while the pedal pressure is being applied. As each nut is loosened, you will probably hear a rush of air or see bubbles escaping at the nut. When they stop, re-tighten each nut and repeat until there are no more bubbles or air. Repeat for each line. After this is done, check your pedal. Should be back to "like new" condition (hard pedal).
The real problem is the air in the brake lines at the ABS block under the hood on the passenger side of the engine compartment. You can't miss it. It has six brake lines attached to it.
After bleeding the lines the old way, using a second person to pump and hold down the pedal before loosening each bleeder valve at each caliper in the following order....PR, DR, PF, DF....you now end up with the mushy pedal. Now go under the hood and have your helper pump up the pedal again. It would be best if you could get your hands on a 10mm "Line Wrench" for this next step. Locate the six lines and their associated nuts. Loosen each nut while the pedal pressure is being applied. As each nut is loosened, you will probably hear a rush of air or see bubbles escaping at the nut. When they stop, re-tighten each nut and repeat until there are no more bubbles or air. Repeat for each line. After this is done, check your pedal. Should be back to "like new" condition (hard pedal).
on the other hand, that air aught to make through the lines out at the brake, in other words you didn't bleed it enough
06-30-2015, 01:32 AM
#67
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Join Date: Jan 2015
Posts: 34
The sponginess of brakes can be fixed by replace vacuum booster. Or try replacing the lines with steel braided lines. Cause with over time as the lines get old they swell up and when you push on the brake they swell even more causing a drop in pedal pressure. You can have a mod done on the master cylinder where you bore it out and use a larger piston for the mc to increase line pressure.
07-02-2015, 05:59 AM
#68
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wow, this is awesome. I didn't know that thing was the ABS thing, I suspected it but that makes sense. What are the other 2 lines? How come this isn't an air in the brake master cylinder problem?
on the other hand, that air aught to make through the lines out at the brake, in other words you didn't bleed it enough
on the other hand, that air aught to make through the lines out at the brake, in other words you didn't bleed it enough
So yes rancur, you're correct. The bleeding wasn't done properly if air was somehow trapped in the abs module! I know that I had bad bleeder plug/screws on the calipers and that was allowing air into the system. I replaced them and no more issues! Also I did replace the calipers when they all began to fail. The pistons were rusted, turns out that Toyota now says to lube the piston where it meets the rubber seal on the caliper with the rubber grease I mentioned earlier. Once I replaced all the calipers the brake pedal was more responsive, more firm than it ever had been even when new! Also replaced the flexible brake hoses, they were not leaking but you could tell they were worn. Brakes feel great now!
and hey you're welcome for telling about that rubber grease! no problem, hope it helps!
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